anyone have an idea why my motor are jerking at the same rate as my ping is fireing? i have the ping on pin 9 so i can just plug it inot the motor shields servo port ( it is just power and pin 9) is this the problem? I know i have a lot of power 8 AA nimh at 2000 mah. my meter says the voltage is over 10 volts. they could be bad batteries. but why the jerking of the motors. it occasionally works right. ( i know i am ranting) any ideas?
Same Problem I had the same problem you had described. I solved it by using two different power sources. I have a 9v battery to run the arduino and 4 AA’s to run the shield. Unfortunately I burned an L293 chip in the process of trying to figure it out. You can also go to her website, I think it’s Ladyada’s teaparty or something like that. She’s quick to respond about problems with her product, she is the one that helped me figure it out.
Power requirements. The Ping needs a 5 volt supply, not 9 volts. Overvolting can burn things up. The RC servos are also rated for 4.8 or 6 volt operation, not 9 volts. It appears that you have 2 packs that have 8 AA batteries each, is that the case? A picture of your set-up would really help. Lady Ada’s motor shield use page has the servos connected to the motor shield, not sure where you have the sonar attached. If the servos are on the motor shield, then they appear to be getting 5 volts. Some sonars when “pinging” can cause a quick current draw that might be responsible for jitter, so a big cap located close to the sonar might help smooth any quick drain. Perhaps something like a 470 uF or larger would work.